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        <h1>
          <span class="m-breadcrumb"><a href="namespacetf.html">tf</a>::<wbr/></span>TFProfObserver <span class="m-thin">class</span>
        </h1>
        <p>class to create an observer based on the built-in taskflow profiler format</p>
        <nav class="m-block m-default">
          <h3>Contents</h3>
          <ul>
            <li>
              Reference
              <ul>
                <li><a href="#base-classes">Base classes</a></li>
                <li><a href="#pub-methods">Public functions</a></li>
                <li><a href="#pri-methods">Private functions</a></li>
              </ul>
            </li>
          </ul>
        </nav>
<p>A <a href="classtf_1_1TFProfObserver.html" class="m-doc">tf::<wbr />TFProfObserver</a> inherits <a href="classtf_1_1ObserverInterface.html" class="m-doc">tf::<wbr />ObserverInterface</a> and defines methods to dump the observed thread activities into a format that can be visualized through <a href="https://taskflow.github.io/tfprof/">Taskflow Profiler</a>.</p><pre class="m-code"><span class="n">tf</span><span class="o">::</span><span class="n">Taskflow</span><span class="w"> </span><span class="n">taskflow</span><span class="p">;</span><span class="w"></span>
<span class="n">tf</span><span class="o">::</span><span class="n">Executor</span><span class="w"> </span><span class="n">executor</span><span class="p">;</span><span class="w"></span>

<span class="c1">// insert tasks into taskflow</span>
<span class="c1">// ...</span>
<span class="w">  </span>
<span class="c1">// create a custom observer</span>
<span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o">&lt;</span><span class="n">tf</span><span class="o">::</span><span class="n">TFProfObserver</span><span class="o">&gt;</span><span class="w"> </span><span class="n">observer</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">executor</span><span class="p">.</span><span class="n">make_observer</span><span class="o">&lt;</span><span class="n">tf</span><span class="o">::</span><span class="n">TFProfObserver</span><span class="o">&gt;</span><span class="p">();</span><span class="w"></span>

<span class="c1">// run the taskflow</span>
<span class="n">executor</span><span class="p">.</span><span class="n">run</span><span class="p">(</span><span class="n">taskflow</span><span class="p">).</span><span class="n">wait</span><span class="p">();</span><span class="w"></span>

<span class="c1">// dump the thread activities to Taskflow Profiler format.</span>
<span class="n">observer</span><span class="o">-&gt;</span><span class="n">dump</span><span class="p">(</span><span class="n">std</span><span class="o">::</span><span class="n">cout</span><span class="p">);</span><span class="w"></span></pre>
        <section id="base-classes">
          <h2><a href="#base-classes">Base classes</a></h2>
          <dl class="m-doc">
            <dt>
              class <a href="classtf_1_1ObserverInterface.html" class="m-doc">ObserverInterface</a>
            </dt>
            <dd>class to derive an executor observer</dd>
          </dl>
        </section>
        <section id="pub-methods">
          <h2><a href="#pub-methods">Public functions</a></h2>
          <dl class="m-doc">
            <dt id="a9f1e839e2a8d3abd0b91ac454f0d078b">
              <span class="m-doc-wrap-bumper">void <a href="#a9f1e839e2a8d3abd0b91ac454f0d078b" class="m-doc-self">dump</a>(</span><span class="m-doc-wrap"><a href="http://en.cppreference.com/w/cpp/io/basic_ostream.html" class="m-doc-external">std::<wbr />ostream</a>&amp; ostream) const</span>
            </dt>
            <dd>dumps the timelines into a <a href="https://taskflow.github.io/tfprof/">Taskflow Profiler</a> format through an output stream</dd>
            <dt id="a59e82cb3f9b0ada38aa1ddea14f14d02">
              <span class="m-doc-wrap-bumper">auto <a href="#a59e82cb3f9b0ada38aa1ddea14f14d02" class="m-doc-self">dump</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="http://en.cppreference.com/w/cpp/string/basic_string.html" class="m-doc-external">std::<wbr />string</a></span>
            </dt>
            <dd>dumps the timelines into a JSON string</dd>
            <dt id="a6102cedbaf2e40f8b8ff916827297198">
              <span class="m-doc-wrap-bumper">void <a href="#a6102cedbaf2e40f8b8ff916827297198" class="m-doc-self">summary</a>(</span><span class="m-doc-wrap"><a href="http://en.cppreference.com/w/cpp/io/basic_ostream.html" class="m-doc-external">std::<wbr />ostream</a>&amp; ostream) const</span>
            </dt>
            <dd>shows the summary report through an output stream</dd>
            <dt id="a6f12a927a328bd594cf6c3c3a6bfe992">
              <span class="m-doc-wrap-bumper">auto <a href="#a6f12a927a328bd594cf6c3c3a6bfe992" class="m-doc-self">summary</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="http://en.cppreference.com/w/cpp/string/basic_string.html" class="m-doc-external">std::<wbr />string</a></span>
            </dt>
            <dd>returns the summary report in a string</dd>
            <dt id="a5e1f63034a96a5a79cef6da412efd203">
              <span class="m-doc-wrap-bumper">void <a href="#a5e1f63034a96a5a79cef6da412efd203" class="m-doc-self">clear</a>(</span><span class="m-doc-wrap">)</span>
            </dt>
            <dd>clears the timeline data</dd>
            <dt id="a8b3b0bee8762af654cfebd2bb2ee98ed">
              <span class="m-doc-wrap-bumper">auto <a href="#a8b3b0bee8762af654cfebd2bb2ee98ed" class="m-doc-self">num_tasks</a>(</span><span class="m-doc-wrap">) const -&gt; size_t</span>
            </dt>
            <dd>queries the number of tasks observed</dd>
            <dt id="a62ccf28199e35748903559848072fc29">
              <span class="m-doc-wrap-bumper">auto <a href="#a62ccf28199e35748903559848072fc29" class="m-doc-self">num_workers</a>(</span><span class="m-doc-wrap">) const -&gt; size_t</span>
            </dt>
            <dd>queries the number of observed workers</dd>
          </dl>
        </section>
        <section id="pri-methods">
          <h2><a href="#pri-methods">Private functions</a></h2>
          <dl class="m-doc">
            <dt>
              <span class="m-doc-wrap-bumper">void <a href="#aa030d8154dd03aea3b8fa8ce42e1151b" class="m-doc">set_up</a>(</span><span class="m-doc-wrap">size_t num_workers) <span class="m-label m-flat m-warning">final</span></span>
            </dt>
            <dd>constructor-like method to call when the executor observer is fully created</dd>
            <dt>
              <span class="m-doc-wrap-bumper">void <a href="#a5debfce27f7e012d22872c134b261c63" class="m-doc">on_entry</a>(</span><span class="m-doc-wrap"><a href="classtf_1_1WorkerView.html" class="m-doc">WorkerView</a> wv,
              <a href="classtf_1_1TaskView.html" class="m-doc">TaskView</a> task_view) <span class="m-label m-flat m-warning">final</span></span>
            </dt>
            <dd>method to call before a worker thread executes a closure</dd>
            <dt>
              <span class="m-doc-wrap-bumper">void <a href="#af3a1630b5b1db5341a239a5d4c12c891" class="m-doc">on_exit</a>(</span><span class="m-doc-wrap"><a href="classtf_1_1WorkerView.html" class="m-doc">WorkerView</a> wv,
              <a href="classtf_1_1TaskView.html" class="m-doc">TaskView</a> task_view) <span class="m-label m-flat m-warning">final</span></span>
            </dt>
            <dd>method to call after a worker thread executed a closure</dd>
          </dl>
        </section>
        <section>
          <h2>Function documentation</h2>
          <section class="m-doc-details" id="aa030d8154dd03aea3b8fa8ce42e1151b"><div>
            <h3>
              <span class="m-doc-wrap-bumper">void tf::<wbr />TFProfObserver::<wbr /></span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#aa030d8154dd03aea3b8fa8ce42e1151b" class="m-doc-self">set_up</a>(</span><span class="m-doc-wrap">size_t num_workers) <span class="m-label m-warning">final</span> <span class="m-label m-danger">private</span></span></span>
            </h3>
            <p>constructor-like method to call when the executor observer is fully created</p>
            <table class="m-table m-fullwidth m-flat">
              <thead>
                <tr><th colspan="2">Parameters</th></tr>
              </thead>
              <tbody>
                <tr>
                  <td style="width: 1%">num_workers</td>
                  <td>the number of the worker threads in the executor</td>
                </tr>
              </tbody>
            </table>
          </div></section>
          <section class="m-doc-details" id="a5debfce27f7e012d22872c134b261c63"><div>
            <h3>
              <span class="m-doc-wrap-bumper">void tf::<wbr />TFProfObserver::<wbr /></span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#a5debfce27f7e012d22872c134b261c63" class="m-doc-self">on_entry</a>(</span><span class="m-doc-wrap"><a href="classtf_1_1WorkerView.html" class="m-doc">WorkerView</a> wv,
              <a href="classtf_1_1TaskView.html" class="m-doc">TaskView</a> task_view) <span class="m-label m-warning">final</span> <span class="m-label m-danger">private</span></span></span>
            </h3>
            <p>method to call before a worker thread executes a closure</p>
            <table class="m-table m-fullwidth m-flat">
              <thead>
                <tr><th colspan="2">Parameters</th></tr>
              </thead>
              <tbody>
                <tr>
                  <td style="width: 1%">wv</td>
                  <td>an immutable view of this worker thread</td>
                </tr>
                <tr>
                  <td>task_view</td>
                  <td>a constant wrapper object to the task</td>
                </tr>
              </tbody>
            </table>
          </div></section>
          <section class="m-doc-details" id="af3a1630b5b1db5341a239a5d4c12c891"><div>
            <h3>
              <span class="m-doc-wrap-bumper">void tf::<wbr />TFProfObserver::<wbr /></span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#af3a1630b5b1db5341a239a5d4c12c891" class="m-doc-self">on_exit</a>(</span><span class="m-doc-wrap"><a href="classtf_1_1WorkerView.html" class="m-doc">WorkerView</a> wv,
              <a href="classtf_1_1TaskView.html" class="m-doc">TaskView</a> task_view) <span class="m-label m-warning">final</span> <span class="m-label m-danger">private</span></span></span>
            </h3>
            <p>method to call after a worker thread executed a closure</p>
            <table class="m-table m-fullwidth m-flat">
              <thead>
                <tr><th colspan="2">Parameters</th></tr>
              </thead>
              <tbody>
                <tr>
                  <td style="width: 1%">wv</td>
                  <td>an immutable view of this worker thread</td>
                </tr>
                <tr>
                  <td>task_view</td>
                  <td>a constant wrapper object to the task</td>
                </tr>
              </tbody>
            </table>
          </div></section>
        </section>
      </div>
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